| Obduction | Cyan | 7/10 | |
| Oceanhorn: Monster of Uncharted Seas | Cornfox & Bros. | 5/10 | |
| Octahedron | Square Enix | 8/10 | |
| Oddworld: Abe's Oddysee - New 'n' Tasty! | Oddworld Inhabitants | 8/10 | |
| Odin Sphere Leifthrasir | NIS America | 9/10 | |
| Oh My Godheads | Square Enix | 5/10 | |
| Oh...Sir!! The Insult Simulator | Vile Monarch | 7/10 | |
| Okami HD | Capcom | 8/10 | |
| Old Time Hockey | V7 Entertainment | 7/10 | |
| Omensight | Spearhead | 7/10 | |
| One Night Stand | Ratalaika Games | 8/10 | |
| One Piece: Burning Blood | Bandai Namco | 6/10 | |
| One Piece: Pirate Warriors 3 | Bandai Namco | 8/10 | |
| One Piece: Pirate Warriors 4 | Bandai Namco | 7/10 | |
| One Piece: Unlimited World Red Deluxe Edition | Bandai Namco | 7/10 | |
| One Punch Man: A Hero Nobody Knows | Bandai Namco | 5/10 | |
| One Upon Light | Rising Star Games | 7/10 | |
| Onechanbara Z2: Chaos | NIS America | 6/10 | |
| Onee Chanbara ORIGIN | D3 Publisher | 5/10 | |
| Onrush | Koch Media | 8/10 | |
| Othercide | Focus Home | 6/10 | |
| Out of Ammo | Zen | 2/10 | |
| Outbreak: The New Nightmare | Dead Drop Studios LLC | 2/10 | |
| Outlast 2 | Red Barrels | 5/10 | |
| Overcooked | Team17 | 8/10 | |
| Overcooked: The Lost Morsel | Team17 | 7/10 | |
| Overpass | Nacon | 5/10 | |